No I dont do either of those things. I am using m3's, and tidy10's, I fill them reasonably slowly I suppose. I dont overfill them, and after filling, I blow through them onto a tissue until it stops producing fluid out the battery end of the clearo.
I definitely did overfill mine once, and the problems started after, so I am hoping to be able to avoid that in the future. I never blew through them, I set them on a napkin for awhile and had no leakage first fill. After second fill leakage occurred but it was momentary. Third fill it seemed like it was pushing fluid out the atomizer as I filled it, which makes some sense as that section is saturated and the air has to go somewhere. I tried doing it slow but it leaked even worse after - in fact it wouldnt quit leaking and I had to decommission it.